Terrorism, vandalism, war and firearms accidents can expose electric power equipment to gunfire. Electric power transformers located in transmission and distribution substations can be particularly vulnerable because they are relatively large targets located in virtually every community. The transformers are typically air-cooled and filled with oil or gel that can escape if the casing is pierced by gunfire resulting overheating, failure and a potential fire hazard. A single substation outage can affect a large number of customers and take several days to repair. Current bullet resistant shields designed for military vehicles and structures do not provide adequate ventilation for electric power equipment. While basic ballistic coverings and panels are commercially available from a number of vendors, there are no systems currently available for conveniently assembling the coverings or panels into wall and enclosures at existing electric equipment locations. As a result, there is continuing need for improved bullet resistant shielding for electric power equipment.